The present invention relates to improvements in methods of and in apparatus for wrapping articles into prefabricated blanks, and more particularly to improvements in methods of and in apparatus for wrapping commodities of the tobacco processing industry (such as parallelepiped arrays or groups of cigarette packets wherein each of two superimposed layers contains five packets) into prefabricated multipanel blanks of cardboard, paper, plastic material or the like. Wrapped arrays of such character are popularly known as cartons. However, the method and the apparatus of the present invention can also serve to wrap other types of commodities, particularly block-shaped commodities such as groups of twenty plain or filter cigarettes, cigars or cigarillos each, into blanks of plastic material or cardboard to thus convert the blanks and the groups into packets, particularly those known as hinged-lid packets.
It is well known to confine groups of cigarettes (normally blocks of twenty parallel cigarettes with or without an inner wrapper of metallic foil or the like) or arrays of cigarette packets in prefabricated multipanel blanks of the type wherein neighboring panels are connected to each other by prefabricated fold lines in the form of elongated grooves, rows of slits, rows of perforations or the like. As a rule, the blanks carry printed and/or other (e.g., embossed) information and are made of cardboard, pasteboard, paper or a suitable plastic sheet material. A blank which is to be converted into the envelope of a carton containing ten cigarette packets normally comprises four elongated panels including two outer panels, an elongated flap attached to the free longitudinal edge of one of the outer panels, and relatively short flaps and tucks at the ends of certain panels other than the one outer panel. All panels are normally connected to the neighboring panels, flaps and tucks by elongated straight fold lines; this enhances the predictability and facility of folding the panels, flaps and tucks relative to each other and contributes to the appearance of the finished product, be it a packet, a carton or any other product wherein one or more commodities are confined in a box-shaped receptacle or container normally having four elongated sidewalls and two shorter end walls. The flaps and tucks are normally bonded to each other and/or to selected panels by a suitable adhesive which can be applied to portions of the surfaces of the blanks during conversion of such blanks into containers.
Presently known apparatus for making cartons, packets and like products of the tobacco processing industry (hereinafter referred to, for the sake of simplicity, as cartons for arrays of cigarette packets) normally comprise a pusher which propels an array of cigarette packets against a fixed blank extending across the path for the advancement and retraction of the pusher. The front side of the array is caused to strike against and to entrain a selected panel of the blank, e.g., through a passage defined by a tunnel, conduit, pipe or mouthpiece (hereinafter called mouthpiece) with attendant folding of additional panels of the entrained blank against additional sides of the advancing array. A drawback of such proposal is that, when the cartons are being produced at a high or very high frequency which is necessary to ensure that a modern production line for plain or filter cigarettes, cigars or cigarillos can process huge quantities of such rod-shaped articles per unit of time without necessitating the utilization of numerous carton forming and filling apparatus, impingement of the front side of an array against a selected panel of a stationary blank invariably causes the generation of pronounced noise. The noise becomes practically unbearable or necessitates a slowdown of the entire production line if the carton making and filling apparatus is installed in a building jointly with numerous additional apparatus. As a rule, a pusher is designed to advance successive arrays and the respective partially converted blanks into the pockets of an indexible turret or another suitable conveyor wherein the conversion of blanks into the containers of finished cartons is completed in a well known manner.
U.S. Pat. No. 5,133,173 (granted Jul. 18, 1992 to Draghetti et al. for "METHOD AND EQUIPMENT FOR WRAPPING GROUPS OF PACKETS") discloses a carton making apparatus wherein two (additional) panels of a stationary blank are pivoted (by means of a mouthpiece or a folding spindle) relative to a first panel between them before the first panel is engaged and entrained by the front side of an array consisting of two layers of five cigarette packets each. The array is caused to enter a stationary folding station wherein the prefolded blank is converted into the finished container of a carton. The noise which is generated on impact of the front side of an array of ten cigarette packets against the first panel of the preformed blank is compounded by noise which is generated by other mobile parts of the carton making and filling apparatus as well as by noise which is generated by other apparatus of a production line so that the overall noise level in a building housing numerous production lines is likely to become unbearable to the employees, especially for longer periods of time.
U.S. Pat. No. 4,653,248 (granted Mar. 31, 1987 to Bergner et al. for "APPARATUS FOR MAKING CARTONS OF CIGARETTE PACKS AND THE LIKE") discloses a carton making and filling apparatus wherein a pusher serves to propel each of a series of successive arrays of cigarette packets against a first panel of a discrete stationary blank which overlies the inlet of a mouthpiece. The blank is entrained through the mouthpiece with attendant folding of additional panels against the respective sides of the array while the latter advances through the mouthpiece and toward and into a deforming member which is thereupon caused to change its orientation through 90.degree. to thus enable a pusher to propel the array and the partially converted blank into a receiving unit wherein the blank is caused to undergo additional conversion into a container of a finished carton. Such apparatus are also likely to generate pronounced noise when a production line employing the patented apparatus is caused to operate at a high or maximum capacity, because successive arrays are being propelled against stationary blanks.
German patent application Serial No. 196 07 419 A 1 (published Sep. 4, 1997 and owned by the assignee of the present application) discloses a carton making and filling apparatus wherein successive arrays of cigarette packets are propelled against stationary blanks with attendant generation of noise, especially if the apparatus is caused to operate at a maximum speed. The apparatus is provided with means for enhancing the appearance of the finished products by ensuring that selected panels of successive blanks are invariably caused to abut against the front sides of the respective arrays, starting with the acceleration of a blank from zero speed and ending with the completion of a forward stroke by a pusher for successive arrays.